Exhibit 99.1 Moleculin Reports First Quarter 2024 Financial Results and Provides Corporate Update HOUSTON, May 13, 2024 /PRNewswire/ -- Moleculin Biotech, Inc., (Nasdaq: MBRX) ("Moleculin" or the "Company"), a clinical stage pharmaceutical company with a broad portfolio of drug candidates targeting hard-to-treat tumors and viruses, today reported its financial results for the quarter ended March 31, 2024. As previously announced, the Company will host a conference call and live audio webcast to discuss the ...

–     Recently announced interim data from ongoing MB-106 study demonstrating Annamycin in combination with Cytarabine (AnnAraC) achieves CRc rate of 62% (54% CR) in 1st and 2nd line AML subjects (N=13) –     Also announced MB-106 reaches 20 subjects enrolled –     Company to host conference call and webcast today, Monday, May 13th at 8:30 AM ET HOUSTON, May 13, 2024 /PRNewswire/ -- Moleculin Biotech, Inc., (Nasdaq: MBRX) ("Moleculin" or the "Company"), a clinical stage pharmaceutical company with a broad p ...

Clinical Trial Results - Annamycin has shown a complete remission (CR) rate of 40% and an overall response rate (ORR) of 55% across all subjects in the Phase 1B/2 trial for AML, with a CR rate of 67% for first-line and 60% for second-line therapies [69]. - The median durability of complete remission (CRc) is approximately 4.9 months, with one death and one relapse reported out of ten CRs [73]. - Annamycin demonstrated no cardiotoxicity in subjects treated, even at doses exceeding the lifetime cumulative anthracycline dose associated with increased cardiomyopathy risk [74]. - The Phase 1B/2 trial for Annamycin in combination with Cytarabine is expected to support a Phase 2 registration-directed clinical trial for New Drug Approval (NDA) [71]. - The company has engaged an independent expert to assess the cardiovascular safety of Annamycin, with ongoing data collection from multiple trials [63]. Regulatory and Patent Information - Annamycin has received Orphan Drug Designation (ODD) from the European Medicines Agency (EMA) for the treatment of AML, enhancing its commercial exclusivity [78]. - The U.S. Patent and Trademark Office issued U.S. Patent number 11,951,118 for Annamycin, with coverage extending until June 2040, subject to regulatory approval timelines [76]. Financial Performance - Revenues for the three months ended March 31, 2024, were $0, consistent with the same period in 2023 [85]. - Research and development expenses decreased to $4.3 million in Q1 2024 from $5.7 million in Q1 2023, a reduction of approximately 24.6% [86]. - General and administrative expenses decreased to $2.4 million in Q1 2024 from $2.6 million in Q1 2023, a reduction of approximately 7.7% [87]. - The net loss for Q1 2024 was $4.97 million, compared to a net loss of $7.92 million in Q1 2023, representing a 37.4% improvement [85]. - Cash used in operating activities increased to $6.72 million in Q1 2024 from $6.02 million in Q1 2023, an increase of approximately 11.7% [91]. - The company recorded a net gain of $1.5 million from the change in fair value of warrant liability in Q1 2024, compared to a gain of $0.04 million in Q1 2023 [88]. - As of March 31, 2024, the company had $0.4 million in cash on hand in Australia, with no known liquidity limitations [90]. - The company expects existing cash and cash equivalents to fund operations into Q4 2024 without additional equity issuance [93]. - The company expensed approximately $0.1 million in general and administrative fees related to an SEC investigation in Q1 2024, down from $0.5 million in Q1 2023 [94]. - The company did not engage in any stock sales during Q1 2024, resulting in no cash provided by financing activities [92]. Research and Development Initiatives - The WP1066 portfolio includes three compounds that have successfully completed Phase 1 clinical trials, with ongoing discussions for further trials in glioblastomas and pediatric brain tumors [81]. - The company is exploring external funding avenues for the WP1122 portfolio, with a final clinical study report submitted in late October 2023 [83]. - Annamycin's unique lipid-based delivery technology aims to improve tissue distribution and reduce toxicity compared to traditional anthracyclines [64].

Patent, once issued, will provide composition protection through 2040, with potential for additional term extension Annamycin is advancing towards pivotal AML study in 2024 and may qualify for an accelerated approval pathway HOUSTON, May 9, 2024 /PRNewswire/ -- Moleculin Biotech, Inc., (Nasdaq: MBRX) (Moleculin or the Company), a clinical stage pharmaceutical company with a broad portfolio of drug candidates targeting hard-to-treat tumors and viruses, today announced it has received an Issue Notification fr ...

HOUSTON, May 8, 2024 /PRNewswire/ -- Moleculin Biotech, Inc., (Nasdaq: MBRX) ("Moleculin" or the "Company"), a clinical stage pharmaceutical company with a broad portfolio of drug candidates targeting hard-to-treat tumors and viruses, today announced that it will report its financial results for the quarter ended March 31, 2024, on Friday, May 10, 2024. Moleculin management will host a conference call and live audio webcast to discuss the operational and financial results at 8:30 AM ET on Monday, May 13, 20 ...

Live video webcast roundtable with members from the Moleculin Management Team and Dr. Tallman to discuss the unmet medical needs in the treatment of acute myeloid leukemia (AML), Annamycin and the Company's AML clinical development program as well as data demonstrated to date Ongoing development progress of Annamycin toward pivotal AML study in 2024 with potential qualification for an accelerated approval pathway HOUSTON, May 2, 2024 /PRNewswire/ -- Moleculin Biotech, Inc., (Nasdaq: MBRX) (Moleculin or the ...

–     Company appoints internationally renowned clinician, Martin S. Tallman, MD as inaugural clinician memberHOUSTON, May 1, 2024 /PRNewswire/ -- Moleculin Biotech, Inc., (Nasdaq: MBRX) (Moleculin or the Company), a clinical stage pharmaceutical company with a broad portfolio of drug candidates targeting hard-to-treat tumors and viruses, today announced the formation of its Annamycin Scientific Advisory Board and inaugural appointment of Dr. Martin Tallman. Dr. Tallman is an internationally renowned clini ...

–     Next-generation non-cardiotoxic anthracycline Annamycin with notable signs of clinical efficacy in AML in combination with Cytarabine achieves preliminary CRc rate of 60% in 2nd line AML subjects in a European clinical trial –     There are approximately 160,000 people with AML worldwide  –     Annamycin continues to show no signs of cardiotoxicity (N=82 across multiple studies); Lower toxicity profile than traditional intensive therapy –     Annamycin is advancing towards pivotal AML study in 2024 an ...

Financial Data and Key Metrics Changes - The company ended the year with approximately $24 million in cash, sufficient to carry operations into the fourth quarter of 2024, despite significant cash outlays for preparations related to the AML pivotal registration study [39] - The market capitalization post-split was around $20 million to $22 million, with a weekly average trading volume of 55,000 shares and approximately 2.2 million shares outstanding [40] Business Line Data and Key Metrics Changes - Annamycin demonstrated a 60% complete response (CR) rate in second-line AML patients, with a 50% CR rate and an additional 10% CRi [10] - In the MB-106 clinical trial, the CRc rate (combined CR plus CRi) for second-line therapy was 60%, with a 10% partial response (PR) rate [28] Market Data and Key Metrics Changes - The company estimates that nearly 60% of AML patients in the U.S. currently lack viable treatment options that could cure their disease or provide lasting remission [13] - The average CR rate for existing targeted therapies is around 21%, which only applies to patients with specific gene mutations, leaving 53% of AML patients without effective treatment options [15][16] Company Strategy and Development Direction - The primary focus for the company is on the AML second-line strategy, with plans to initiate a pivotal registration study for Annamycin this year [11][12] - The company aims to establish a pathway to approval for Annamycin, which is positioned as a next-generation treatment with no cardiotoxicity, potentially addressing a significant unmet need in AML and other cancers [12][22] Management's Comments on Operating Environment and Future Outlook - Management expressed confidence in the efficacy of Annamycin, stating that it outperforms every asset approved in AML and that the gap between the company's current market cap and its potential value is unjustifiable [47][48] - The company plans to meet with the FDA to discuss data and establish a concrete approval pathway for Annamycin, with expectations for significant developments in 2024 [51][52] Other Important Information - The company is preparing to form a larger and more focused scientific advisory board to guide its pathway to new drug approval [49] - Management highlighted the importance of addressing the unmet medical need in AML, which has been recognized by key opinion leaders in the field [50] Q&A Session Summary Question: What is the final patient number for first-line patients in this new Phase 2 cohort? - The company clarified that the initial pivotal registration trial will focus on second-line patients, with a first-line study planned for additional indication after initial approval [53][54] Question: What do you need to see in the Phase 2 first-line patients to make the decision to go forward with that trial? - The efficacy benchmark for the Phase 2 first-line patients is expected to be around 40% CR [61] Question: Why not just push for first-line now? - The management explained that the regulatory time to approval is shorter for second-line therapies due to the significant unmet medical need, which allows for a faster path to market [63][64] Question: What feedback has the FDA provided regarding dosing? - The management indicated that the current dosing strategy has yielded impressive results without toxicity, and they are focused on getting to market as soon as possible [75][77]

"Over the course of 2023 we established a significant growing body of positive clinical and encouraging safety data for Annamycin that continues to strengthen our confidence in the potential of our next generation, non-cardiotoxic chemotherapy in the treatment landscape for hard-to-treat cancers and viruses," commented Walter Klemp, Chairman and Chief Executive Officer of Moleculin. "Building off of our momentum, we are laser focused on driving our priority pipeline programs toward key data milestones in th ...